Using this soap dispenser is easy. Just wave your hand in front of the built - in motion sensor, and it will automatically dispense 0.04 ounces of soap. Before installation, make sure you have a 1 - inch diameter opening in the counter top near the sink. Install the four D - size 1.5 - volt batteries (not included) to power the unit. Keep an eye on the blue and red LED lights. If they indicate a problem with the battery charge or soap viscosity, take appropriate action. You can fill it with 54 ounces of soap, detergent, or lotion with a viscosity between 100 and 3500 MilliPascals per second. For maintenance, it's pretty straightforward. Since it's designed for high - traffic areas, check the soap level regularly and refill when needed. Also, clean the dispenser occasionally to keep it looking good and functioning properly.